大豆低聚糖及其功能组分对体外条件下肉仔鸡粪臭素产量及盲肠菌群组成的影响

发布时间：2018-02-07 14:10

  本文关键词： 粪臭素 大豆低聚糖 盲肠菌群 体外发酵 肉仔鸡　出处：《沈阳农业大学》2017年硕士论文　论文类型：学位论文

【摘要】：粪臭素是微生物降解L-色氨酸(L-try)的代谢产物,是引起鸡排泄物产生恶臭的主要物质之一。大豆低聚糖(SBO)是以大豆及其加工副产品为原料生产的,含有一定量的水苏糖(STA)、棉子糖(RAF)和蔗糖(SUC)等低聚糖的产品。本试验旨在研究SBO及其功能组分对体外条件下肉仔鸡粪臭素产量的影响,并探索其微生物学机制。试验采用单因素完全随机试验设计,以42日龄肉仔鸡盲肠内容物为菌源,分别设SUC、STA、RAF、SBO和对照组,每组3个重复。体外发酵液的体积为200mL,L-try的添加量为250 μmol/L,各处理组在对照组的基础上添加等量的SBO、SUC、RAF、STA粉末,每个处理组都有不加L-try,但其他成分都相同的空白对照,以便对吲哚和粪臭素的含量进行校正。利用ANKOMRFS体外产气系统,39℃C厌氧培养24h,记录累积产气量,测定发酵体系中吲哚、粪臭素及有机酸的浓度、pH值及菌群结构和主要菌群数量。试验结果表明:(1)粪臭素及发酵参数:①发酵至24h,SUC、STA、SBO组累积产气量极显著高于对照组和RAF组(P0.01),对照组产气量最低;②SBO、SUC和STA组发酵液吲哚浓度分别比对照组降低了98.15%、97.72%和94.17%(P0.01);③SBO、SUC、STA和RAF组发酵液中粪臭素浓度分别比对照组降低了79.04%、71.88%、70.28%和62.42%(P0.05);④SUC、STA和SBO组L-try降解率极显著低于RAF和对照组(P0.01);⑤SBO及其功能组分对发酵液乙酸浓度影响不显著(P0.05),对乳酸浓度和pH值有极显著的影响(P0.01)。SUC组乳酸浓度极显著高于其余各组(P0.01),其中,比对照组高出75.44%。对照组的pH值最高(7.46),极显著高于RAF之外的其余各试验组(P0.01)。(2)发酵液菌群结构:采用PCR-DGGE技术研究了发酵液菌群结构差异,表明,各组菌群多样性指数差异不显著(P0.05);SBO组菌群均匀度显著低于对照组(P0.05);各试验组菌群丰富度显著高于对照组(P0.05);SBO、STA、RAF组发酵液的相似性均高于对照组;试验组有3条特异性条带,相似菌分别为布劳特氏菌属(Blautia producta)、副拟杆菌属(Parabacteroides distasonis)、路氏乳杆菌属(Lactobacillus reuteri)细菌的增值,说明添加低聚糖能够通过促进以上细菌的增长而降低吲哚、粪臭素的产生。(3)发酵液菌群数量:采用荧光定量PCR(qPCR)技术测定了发酵液主要菌群数量。表明,总菌数量由高至低依次为:SBO组STA组SUC组RAF组对照组;大肠杆菌数量由高至低依次为:SBO组STA组SUC组RAF组对照组;双歧杆菌的数量由高到低依次为:对照组SBO组SUC组STA组RAF组。各组总菌、大肠杆菌和双歧杆菌的数量无显著差异(P0.05);乳酸菌数量由高到低依次为:SUC组STA组SBO组RAF组对照组,其中SUC、STA和SBO组乳酸菌数量显著高于对照组(P0.05)。发酵液吲哚浓度与总细菌数量之间为显著的负相关(P0.05),吲哚和粪臭素浓度与乳酸菌数量之间为显著的负相关(P0.05)。综上,在肉仔鸡盲肠菌群发酵液中添加SUC、STA和SBO显著降低了粪臭素和吲哚的浓度,影响体外发酵参数,并通过提高发酵液菌群丰富度和增加乳酸菌的数量,降低粪臭素的浓度。降低粪臭素效果优劣依次为:SBOSUCSTA。
[Abstract]:Skatole is microbial degradation of L- tryptophan (L-try) metabolite is caused by chicken excreta odor. One of the main material of soybean oligosaccharides (SBO) in soybean and its processed products for the production of raw materials, stachyose contain a certain amount of (STA), raffinose and sucrose (SUC (RAF) etc.) oligosaccharide products. This experiment was conducted to study the function of SBO and the influence of components on odor pigment production conditions in vitro broiler manure, and explore its microbiological mechanisms. Using a single factor completely randomized design, with 42 day old broiler caecum content as the bacteria source, respectively SUC, STA, RAF. SBO and control group, each with 3 replicates. The in vitro fermentation liquid volume is 200mL, the content of L-try was 250 mol/L, each treatment group added SBO, on the basis of the control group SUC, RAF, STA powder, each treatment group has no L-try, but other components of the same blank for According to the content of indole and skatole was corrected by ANKOMRFS. In vitro gas production system, 39 C C 24h anaerobic culture, record the cumulative biogas fermentation system, determination of indole, skatole and organic acid concentration, pH value and flora structure and main microflora. Test results show that: (1) scatol the fermentation and fermentation parameters: 1 to 24h, SUC, STA, SBO group, the cumulative gas production was significantly higher than the control group and RAF group (P0.01), the control group of SBO, the minimum gas production; SUC group and STA fermentation liquid indole concentrations were lower than the control group 98.15%, 97.72% and 94.17% (P0.01); SBO SUC, STA, and RAF group in the fermentation liquid of skatole concentrations were lower than the control group 79.04%, 71.88%, 70.28% and 62.42% (P0.05); the SUC, STA and SBO group, the degradation rate of L-try was significantly lower than that in RAF and control group (P0.01); the SBO and the functional components of the fermentation broth of acetic acid concentration was not significant (P0.05), milk 閰告祿搴﹀拰pH鍊兼湁鏋佹樉钁楃殑褰卞搷(P0.01).SUC缁勪钩閰告祿搴︽瀬鏄捐憲楂樹簬鍏朵綑鍚勭粍(P0.01),鍏朵腑,姣斿�圭収缁勯珮鍑�75.44%.瀵圭収缁勭殑pH鍊兼渶楂，

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